Improvement in adding-machines



.lOl-IN GROESBECK, OF PHLADELPHIA, PENNSYLVANIA.

Letters Patent No. 100,288, la-ted March 1, 1870.

IMPROVEMENT IN ADDING-MACHINES.

The Schedule referred to in these Letters Patent and making parl: of the same,

-To all whom it may concern:

Be it known that 1, JOHN Gnonsnon, of the city of Philadelphia, and State of Pennsylvania, have invented a new and useful Improvement in Adding-Machines; and I do dereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings and to the letters of reference marked thereon.

My invention relates to combining two or more wheels, having a series of numbers arranged in a snitable case, which is provided with a cap-plate that has segmental openings, partly covering the numbers on the wheels, to bring them in view ofthe operator, and there heilig indexesof ten digits at one edge of the openings, arranged to correspond with the numbers on the wheels, to be used in conjunction therewith; and consists of a peculiarly-formed tappet, in combination with a multiplier wheel, the tappet being held in place by a segmental curve on one edge, near its center of motion, coming in contact with a segmental projection ofthe center-pin, on which said wheel turns, and-held thereto by means of a spring, when the tappet isL to bear against a tooth of an advanced wheel of the series, to carry said wheel around thc distance of one tooth.

After this action ofthe tappet, the segmental curve above mentioned passes off the segmental projection of the center-pin, and the tappet is forced away from the numbered wheel just acted upon by the force of the spring, so as to prevent its catching on the forward tooth, or the .one in advance of the multiplier-wheel.

In the accompanying drawings, which make a part of this specification- Figure 1 is a top view of the improved machine.

Figure 2 is a like view, the cap-plate B being rcmoved from `the bed-plate A.

Figure 3 is a longitudinal section, through the line a b of tig. 1.

Figure 4 is an isometrical view of the cap-plate l5, in a reversed position.

Like letters in 'all the figures indicate the same parts.

A is the bed-plate, to which the several parts of the machine are attached.

B is the cap-plate, which is shown in detail in iig. 4.

I have represented in the drawings a series of wheels, C O' C, which turn freely on the center-pins a a' a..

The wheels C and U have three series of the ten digits conccntrically arranged, as seen in Iig. 2, and the wheel C a series of numbers, commencing with a cypher, and running up to 29.

lt may be seen, however, that by increasing the size of the wheels the height of the numbers may be iucreased in proportion.

The numbers of all the wheels correspond with the numbers of teeth or cogs b which connect the wheels together.

The cap plate B has segmental slots c c' c" directly over the wheels C C' C" beneath them to bring the numbers on the wheels in view of the operator.

At one edge of the slots o c' the ten digits arc arranged in the same order as on the wheels C C as indexes to the numbers on the wheels.

There are openings ll (l l in the cap-plate B, over the wheels' C C C", beneath which the sums of thc numbers on the lat-ter are brought, as hereinafter described.

D is a mult-iplier-whecl, having ten teeth, which gear into the teeth ot' the wheel C, and which carries a tappct, E, which, in every revolution of the wheel D, is brought into contact with one of the teeth l of the wheel C', to carry the latter around the distance of one tooth.

' The tappet has a partial turn on the pin e which projects from the side of the wheel D, and bollire it reaches one of the teeth of the wheel C the segmental curvcf, on its rear edge, gently comes into connection with the segmental projection g of the pin lr, on which the wheel l) revolves, and is thusbrought into thc right position to fact on the wheel G.

F is a spring, whose resilient part'bears-against thc forward edge ot' the tappet E, and keeps the segmental curve f against the segmental projection g, around which it slides, until the tappet passes the tooth, with which it engages, of the wheel G', and then bears the tappet away from the said wheel to prevent it striking the next tooth, the curve f being by this time disengaged from the projection g, and thus allowing thc tappet to have a partial turn ou its center pin c.

There is a multiplier-wheel, D', having ten teeth, which gear into the teeth of the wheel C'.

Projecting upward from the side ot' the said wheelv D' yisa pin, h', which in every revolution of the wheels' is brought to bear against one of the teeth of the, wheel G, to carry said wheel around the distance of one tooth.

There are pawls G G' which carry friction-roller i. i i", which bear between contiguous teeth of the wheels C C C", to hold the latter accurately in position when stopped, the pawls being actuated by the springs H H H respectively.

Auxiliary to said pawls are the spring-detents I 1'1", which catch respectively against the front edges ofthe teeth of the wheels G G C", to prevent the latter being carried around with too much force by their momentum, while the pawls Gr G G" give accuracy to their stoppages.

The springdctent I, instead of bearing against the teeth of the wheel C, as the others against their wheels, bears against the teeth of the wheel D, as represented, and operates on both wheels.

rlhc detents I l I" are so placed that when the wheels C C C are at rest their teeth shall not touch the teeth of the multiplier-wheels D D, and so operate as to prevent the wheels i. i of the pawls G G' G" stopping on the ends of the teeth of wheels, instead of between the teeth. They also prevent the movement ofthe wheels C C C by mere momentum, which could not be eii'ected by the springs H H H, unless they were made so strong as to prevent an easy movementof said wheels.

The operation is as follows:

The wheels C C C" are set by means ol' a pointer, so that 0 appears at each of the openings d. This is done by the pointer being placed respectively in the concentric slots c fof the cap-plate B.l By bearing against a tooth the wheel is moved around the requisite distance. rlhen the wheel is moved from the numbe to be added to the bottom of the index. For instance, to add 35 and G3: after setting the wheel at 0, insert the pointer at 3 in the segmental slot correspond ing to the column to be added, and carry down until stopped at the bottom of the index, then at 5 at the -98 will appear.

In the drawings, but two wheels having indexes are given; but the same principle may be applied in the use ot' a greater number of wheels, until 3, 4, or more columns may be added at a time.

What I claim my invention, and desire to secure by Letters Patent, is

The tappet E, when constructed with the segmental curve f, and combined with the multiplier-wheel.D, spring F, and segmental projection g oft-11e center-pin la, and arranged to operate in relation to the wheel C', substantially as specified.

In testimony that the above is my invention, I have hereunto set my hand and aflixed my seal this 14th day of May, 1869. v

JOHN GROESBEGK. [L. s]

Witnesses:

STEPHEN Us'rlcn, THOMAS J. BEWLEY. 

